This application claims the benefit of New Zealand Patent Application No. 511009, filed Apr. 9, 2001, the disclosure of which is hereby incorporated herein by reference.
The present invention relates generally to a threaded fastening device, in particular the invention relates an assembly of parts, which co-operate to provide a threaded fastening device.
Conventional fastening devices such as integrally formed threaded nuts are well known and have been used for many years.
These conventional nuts are applied to a threaded member such as a bolt and together the nut and bolt co-operate to fasten or secure an object between the bearing face of the nut and the bearing face of the bolt.
One of the difficulties with these conventional nuts is that they can at times be very difficult to separate from a bolt or threaded member. These difficulties typically arise for a number of reasons. These reasons include
the accumulation of grit and grime in the thread,
the rusting of the threaded member or nut to some extent,
the burring or rounding of the nut or bolt, or
damage to the thread or nut, such as cross threading.
All these situations mean that at times it can be very difficult to unwind a nut from a bolt or threaded member.
Other difficulties are often experienced through the amount of time that is required to fasten or unfasten a nut from a bolt. These difficulties arise if the bolt or threaded member is particularly long, it can take a considerable period of time to unwind the nut from the thread. Also, in some situations such as temporary fencing and scaffolding, the removal of nuts from bolts can be a very time consuming exercise. Another known difficulty of conventional nuts and threaded members is that sometimes the nuts are in places making it difficult to reach with hands or tools.
This often makes it a time consuming job to tighten or unwind a nut where rotation of the nut itself can only be done in small increments because of a space limit in which to turn a tool such as a crescent or the like.
It is an object of the present invention to overcome some of these known difficulties and to provide a nut which can be easily removed from a threaded fastening member, or which at least provide the public with a useful choice.
In the first aspect the present invention provides a threaded fastening device assembly including,
an outer member having an upwardly extending and circumferentially disposed body with a non-threaded inner and outer surface,
at least two inner members, each inner member having an internal surface which is threaded and an outer surface that is complimentary in shape to said inner surface of said outer member,
wherein, said outer member is adapted to be slideably engageable with said inner members and wherein in use, said fastening assembly is rotatable and engageable with a complimentary threaded fastening shaft.
Preferably, each inner member further includes a locking means which is adapted to engage with a complimentary locking means on said outer member.
Preferably the locking means on the inner member is a rib which engages with a corresponding groove on said outer member.
Preferably the body of said outer member is adapted and dimensioned in shape to include a recess extending circumferentially around the base of said body, which is adapted to receive a complimentary flange extending from each of said inner members.
Preferably the external surface of the outer member is shaped to suit the application to which the fastening assembly is to be put. One such preferred shape is a hexagonally shaped outer member.
In a second aspect of the present invention there is provided a kit of parts for a threaded fastening device assembly as defined above, wherein said kit includes an outer member and at least two inner members as defined above.
Preferably, the kit includes a retaining member which retains each of the inner members in fixed location to each other.
Preferably, the retaining member retains said inner members in a spaced apart relationship, such that in use, said retaining member and inner members can be slid down the length of a threaded shaft and positioned to receive and engage with said outer member. A sacrificial wire retaining the outer member and the inner members in a spaced apart relationship would be one such preferred embodiment.
In a further aspect of the invention there is provided an outer member adapted to receive two or more inner member portions as defined above.
In a further aspect of the present invention, there is provided an inner member portion, wherein two or more inner member portions together are adapted to be slideably engageable with an outer member as defined above.
Further aspects of the invention will become apparent from the following description and figures given by way of example only, wherein: